Drop In AdSense CTR

Good morning all, please I need urgent help.

Close to the end of last month, the CTR of my AdSense dropped from about 1.6 to 0.8 and has not dropped to 0.2. I’ve been hoping it will rise for days now, but it’s not and it’s really affecting my earnings badly. I haven’t made any change on the site recently and I’ve tried experimenting other ads sizes since then. What can I do to take it back to the right rate?

do you know factors that might make your ctr to increase or decrease? If not, you might have to start from there…

Please sir, what are the other factors?

I know that the following affects:

Ads placements/ position Ads Sizes Non contextual ads etc

And I heard of ad blindness too and I’ve tried to tackle that by changing sizes, units, colors etc. Please what else do I need to look into?